Watchman{40 s tour alarm system

ABSTRACT

An alarm system establishes, according to a preset program, the order and the minimum time schedule to be followed by a watchman in checking control stations on his vigilance rounds. The watchman carries a portable control assembly which must be plugged into each fixed control station in the proper order and after the elapse of a minimum time before the portable control assembly will shift to correspond to the next fixed control station. If the entire round is not completed and the portable control assembly plugged into a main control station within a predetermined time, an alarm will be triggered.

United States Patent [191 Restrepo [ll] 3,774,193 1 Nov. 20, 1973WATCHMANS TOUR ALARM SYSTEM [76] Inventor: Tulio Vasquez Restrepo,Carrera [52] US. Cl 340/306, 340/3091, 346/144 [56] References CitedUNITED STATES PATENTS 3,579,221 5/1971 Ashley 340/306 X PrimaryExaminer.lohn W. Caldwell Assistant Examiner-William M. WanniskyAtt0rney-Alvin Browdy et al.

[5 7] ABSTRACT An alarm system establishes, according to a presetprogram, the order and the minimum time schedule to be followed by awatchman in checking control stations on his vigilance rounds. Thewatchman carries a portable control assembly which must be plugged intoeach fixed control station in the proper order and after the elapse of aminimum time before the portable control assembly will shift tocorrespond to the next fixed control station. If the entire round is notcompleted and the portable control assembly plugged into a main controlstation within a predetermined time, an alarm will be triggered.

9 Claims, 7 Drawing Figures WATCHMANS TOUR ALARM SYSTEM FIELD OF THEINVENTION The present invention relates to an alarm system for use inconjunction with a watchmans vigilance rounds and more particularly to asystem including a series of fixed control stations each having adifferent predetermined electrical reactance associated therewith and aportable control assembly which will only function if plugged into eachcontrol station in a predetermined order and minimum time schedule.

SUMMARY OF THE INVENTION This invention relates to a portable assemblycomprising mechanical, electrical and electronic means cooperatingtogether in order that a watchmans rounds may be carried out in a presetpath and time program.

A series of fixed control stations are arranged at key points around abuilding or area to be protected. The watchman carries a portableassembly which is programmed to advance only when the correct controlstation is approached after a predetermined minimum time lapse betweenstations.

A timer in a central control unit is started when the watchman beginshis rounds. Unless the watchman returns withina predetermined timeperiod, a general alarm is triggered. The portable assembly which thewatchman carries will only deactivate the central control unit timer atthe end of his rounds if all of the fixed control stations have beenchecked in the predetermined order with the minimum time spent betweenstations.

A preferred embodiment of the present invention will now be summarized.A number of control stations is arranged along the round of a watchman.Each control station comprises a sheet metal box housing an electricalelement, useful as an electrical reference sample, which is encased andhidden within a plastic material body. The box is provided with atwo-pole plug socket electrically connected to the two terminals of theelectrical reference sample.

A portable control assembly, comprising mechanical, electrical andelectronic means, establishes, according to a preset program, the orderand the minimum time schedule to be followed by the watchman to checkthe full array of control stations. The portable assembly has a two-poleplug tap connected thereto by a flexible cable and suitable forconnection to the control station socket. Also the portable assembly hasa button which must be pushed down by the watchman each time he connectsthe portable assembly to each control station in order to automaticallycompare the electrical value of the electrical element or samplereference element with the electrical value of a comparison elementcated within the portable assembly. In the event that the reactancevalues of the sample reference element and the comparison element arethe same, a switching key of the assembly is shifted to a new comparisonelement to be compared with the sample reference element in the nextcontrol station. A device cooperating with an electronic circuit of theportable assembly shall establish the minimum lapse of time that mustelapse to perform the next comparison. Each properly checked controlstation will shift the switching key finger which marks the controlstation to be checked by means of a sequential numbering shown throughan inspection opening.

When the watchman checks the penultimate control station, an indiciawill appear through the assembly inspection opening, the letter R forinstance, which means that when checking the last control station anelectrical pulse will be sent via a connecting line to a central controlunit causing an electronic time delay means, to be describedhereinafter, to cancel the time it had built-up. As stated above, thecentral control unit is provided with an electronic time delay devicewhich is set by the security monitor to a lapse of time that would allowthe watchman to carry out his full watchman round. Whether due towatchman oversight or any other reason he does not reach the timeresetting station in the greatest preset time, twenty minutes forinstance, one or several suitably located alarm lamps will be activatedthus showing the watchman that the preset time for completing his roundis about to elapse. If in spite of the luminous advice the restorationis not carried out within an additional time, three minutes for.instance, a loud sound alarm will be activated and simultaneously aninternal counter provided in the central control unit will record thefailure. If in spite of the sound signal the restoration does not occurwithin another preset lapse of time, three minutes for instance, ageneral sound alarm will be excited or an electrical signal will besentto a central station thus indicating an emergency condition.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation cross-sectionalview of the portable assembly.

FIG. 2 is an enlarged cross sectional view showing in detail themechanical means for controlling the operation of the sprocket wheel inthe portable assembly.

FIG. 3 is a top plan view showing the arrangement of the selector keyand pulse generating means comprised in the portable assembly.

FIG. 4 is a plan view showing the arrangement of the selector keycooperating with the time delaying means.

.FIG. 5 is a detail of the electrical circuit used for performing thechecking operation.

FIG. 6 is a circuit diagram of a portion of the circuit of FIG. 5 inWheatstone bridge form.

FIG. 7 is a block diagram of the alarm system connected to the centralstation.

DESCRIPTION OF THE PREFERRED EMBODIMENT When the watchman wishes toeffect a comparison at a control point,'he pushes down the button 1which shifts the axis 36 thereof through fixed bushings 9 and 10 locatedat fixed levels in such a way that a projection 20, projecting from axis36, presses an arm 6, pivotable about shaft 24, downwardly, causing itto pivot from the position shown by dashed line 21 to that shown bydashed line 22, stopping against movable stop' 18 mounted on theassembly housing. In this way pawl 7 located on arm 6 jumps over onetooth, then' goes into one recess and partially jumps over the nexttooth. Simultaneously, by this step, a portion 2 of axis 36 having thegreatest diameter is moved downwardly, thus closing a switch 3 therebyactivating the electronic circuit which performs the comparison andcontrol process as will be explained hereinafter.

In the event that the comparison process meets the particular designfeatures of the system, i.e., if the control station order was followedwithin the proper time schedule, a correct comparison pulse is generatedwhich activates the electromagnet 13 long enough to cause the retainingarmature 12 to release the sprocket wheel 11 thus permitting theadvancement of one or two of the teeth as required, as it will beexplained hereinafter.

When the button 1 is released, the arm 6 turns back urged by a spring 4which is joined by one end thereof to a projection affixed to thehousing. As the arm 6 in its back movement engages the sprocket wheel 11by means of the pawl 7, the wheel will be advanced through the anglecomprised between one recess and the next one, i.e.,- the sprocket wheelwill advance the necessary extent to bring one signal number intoregister with the inspection opening shown in the drawing registeringwith the indicia R. Button 1 will be snapped back by the spring 8 up toits retaining stop. An adjustable stop is useful for accurately settingthe rest position of the arm 6. A roll 16 arranged on one end of an arm15 is pressed on the recesses between teeth of the sprocket wheel 11 bymeans of a tension spring acting on the other end of arm 15. The roll 16serves to accurately clamp in place the wheel after each advancingmotion of the wheel thus preventing the rotation thereof that otherwisewould be caused by the jerking of the portable assembly.

By turning the movable stop 18 through a 180 extent in the direction ofthe arrow, around its offset pivot, a greater downward displacement ofthe arm 6 is allowed thereby attaining an advancing action on thesprocket wheel 11 through a distance corresponding to a two toothseparation since with such an arrangement the pawl 7 is permitted tofall in the next recess, i.e., it jumps over two teeth.

Sprocket wheel 11 is provided with an offset cylindrical projection 19protruding from both faces thereof. As will be explained hereinafter inconnection with the description of the electrical alarm system, when thesprocket wheel 11 goes from the R position shown in FIG. 1 to the 1position, i.e., through a one tooth advancement, it must be donesuddenly, regardless of whether button 1 is released slowly or quickly.When arm 6 starts to advance the sprocket wheel 11, axis 36 is fullypushed down and therefore its lower portion stops the angular path ofthe projection 19 thus preventing the sprocket wheel 11 from turningexcept only through a few degrees. When the axis 36 rises and clears thepath of projection 19 the projection 20 on the axis 36 will have movedto some distance from arm 6 since the wheel 11 having been blocked, theupward displacement of the arm 6 had been impeded due to the engagementbetween pawl 7 and the wheel 11. Therefore when the path of projection19 is cleared both the wheel and the arm will suddenly advance incounterclockwise direction until the arm strikes against the projection20 of the axis 36.

When the wheel passes from R position to position 1, i.e., whenadvancing one additional tooth to the position shown in FIG. 1, theportion of projection 19 on the rear of wheel 11 causes the element 25,slidingly mounted within a fixed guiding bore, to be radially shiftedoutward thus pushing the button of a clock device 28 setting the same tozero time. The member 25 simultaneously drives the armature 29permitting the motion of a contact 30 to be explained hereinafter.

A button 31 is slidably lodged within a sleeve provided in the housing26 for being pushed by a key after one full wheel revolution, i.e.,after one watchman round, in order to close the contact 30. When contact30 is closed, the preset time schedule between control stations iscancelled. When pushing down the button 31 until a pawl 32 is engagedwithin a groove in the bottom, the contact 30 is closed and its free endbears against the bottom end of the armature 29. When the rear portionof the projection 19 strikes against the sliding member 25, the armature29 pivots against the tension of spring 33, releasing contact 30 andpermitting the contact 30 to open due to the flexibility of the support35 which flexibly connects the switch 30 to the frame 26, as shown inFIG. 2.

Referring to FIG. 3, the shaft 24 which is fixedly joined to the wheel11 is also fixedly attached to an electrically insulating disc bearing acontact finger 49 for a ring 44 acting as a collector ring.

A disc 43 is constructed from insulating material and is fixedly mountedparallel to the back of the sprocket wheel 11. A switching key which ismounted on the disc 43 is provided with a number of contact positionsequal in number to the number of teeth provided on the wheel 11 with anadditional position positioned between the contact positions numbered 19and 1 and which performs the function of restoring the system.

Each one of the contact positions 47 is coupled to a capacitor seriesconnected to a resistance. All of the resistances are connected togetherby the outer connector thereof thus forming a common connecting ring.The finger 49, which is fixedly joined to the ring 44 and the disc 45which is in turn fixedly joined to the shaft 24, goes from one contactposition to the next, each time the sprocket wheel advances one tooth. Aterminal 41 is connected to a sliding contact 46 which slides on thering 44. As the connecting finger 49 may attain several contactpositions, this makes it possible that, at the terminals 41 and 42,there appear the several values of the resistance-capacitor sets whichare connected to the nineteen positions of the embodiment shown in thedrawing as the finger 49 goes over the several contact positions due tothe advancing of the sprocket wheel. When the finger 49 passes from theR position shown in FIG. 3 to the contact position 1, it transientlycontacts the contacting position 50 because this is an intermediateposition between two stationary positions. Thus, the contacting position50 transiently bridges the terminals 41 and 42 which causes a restoringpulse to be generated.

Between the sprocket wheel 11 and the disc 43, and parallel thereto,there is fixedly mounted a disc 53 (FIG. 4). A connecting finger 48being fixed to a ring 54 and a disc 55 which is in turn fixedly attachedto shaft 24, goes from one contact position 57 to the next one, eachtime the wheel is advanced by one tooth. A terminal 51 is connected to asliding contact 56 which slides on the ring 54 and, as the contactfinger may attain several contact positions, this makes it possiblethat, at terminals 51 and 52, there appear the 20 values correspondingto the resistances connected by one end to each one of the contactpositions 57 and by the other end to a common connecting ring connectedto terminal 52. Each resistance value, as will be fully explainedhereinafter, sets the minimum time for the watchman to spend going fromone control station to the next one.

DESCRIPTION OF THE PREFERRED ELECTRONIC CIRCUIT As stated hereinbefore,each control station has an electrical element therein, connected to aplug socket, such electrical element serving as a reference sample forperforming the comparison carried out by means of the portable assembly.In the preferred embodiment of the invention, the electrical element iscomprised of an electrical means or group of electrical means providingsome amount of electrical reactance to the electric current supplied tothe portable assembly, such a group being comprised of a resistor and acapacitor series connected togetherat 61 and their free ends joined to aplug socket 63 to be connected with the plug 27, in turn suitablyelectrically connected to the electrical circuit of the portableassembly, as seenin FIG. 5.

The electrical circuit used performing the checking operation issubstantially based on the so-called Wheatstone bridge arrangement asshown in the diagram of FIG. 5 and FIG. 6. In the diagram of FIG. 5 thereactance set is fed from an AC source or oscillator 70 connected to thebattery 72 of the portable assembly through a servicing switch 73.According to a rated frequency of oscillator 70, the group 64 has thesame reactance as the group 65 and therefore, if the group 61 located inthe control station is of the same reactance value as that of the group66 belonging to the portable man is effecting the comparison operation,he holds the button I pushed down (FIG. I) the oscillator 70 and theunit 69 will be energized. As previously stated, the oscillator 70supplies alternating current for the comparison process and unit 69 isso featured as to send current to magneto 13 when a comparison processdoes not show potential difference between points 41 and 76.

Thus, the system acts as an inverse amplifier operating in such a waythat when electrical current does appear between points 41 and 76, itdoes not send electrical current to magneto 13 arranged for attractingthe armature 12 (FIG. 1) and thus does not release the sprocket wheel 11allowing it to advance. In the event proper comparison is obtained,i.e., the sample element 61 matches the electrical reactance of element66, an electrical pulse will be sent by unit 69 to magneto 13, providedthe switch 3 is in on position and the time delay means 74 allows theelectrical flow to the positive lead of the power supply 72 as will beexplained hereinbelow. A set capacitor-resistance 68 comprises a highcapacitance and a high rated resistance and the purpose thereof is toprevent the watchman from charging the battery 72 when leaving button Ipushed down, since magneto I3 will receive an electrical short pulsewhile discharging the group 68. It is the object of the resistance ofthe group 68 to slowly discharge the capacitor when the reading unit 69has no current.

The sample electrical group 61 and the comparison electrical group areeach. comprised of a series connected resistance and capacitor, havingas their main purpose to make it difficult to determine the resistancevalue through electrical measuring.

The time/delay means 74 is designed to establish the minimum time withinwhich the watchman must perform one comparison and the next one, thuscausing him to stay between the concerned stations for the desiredpreset time. For each value of the groups of reactance 66 of theselector key 43, there will be one value of resistance 77 because bothselector keys are controlled' by the shaft 24. For sake of simplicity inthe drawing, in FIG. 5 each key was depicted as having four positions,instead of the twenty positions. In the preferred arrangement of theinvention the time delay means 74 is electronic in nature and itsoperation is based on a resistance-capacitor set, generally termed RCset, wherein the capacitor has a constant value and the resistancewill-have values which may change for each 57-position of the selectorkey 53, such that for each value of the set resistance, there willcorrespond a distinct time for the time delay cycle of the time delayingmeans 74. As a further feature, such time delaying means starts a newtime delay cycle each time the circuit of the resistance is opened, thatis, each time the finger 58 of the key 53 changes from onecontactposition to the next. The several resistance values will appearat the terminals 51 and 52 and therefore, when switch 30 is actuated byinwardly shifting the button 31 (FIG. 2), the former will remain closedas .explained above until the watchmans round ends, that is, when thesprocket wheel 11 goes from the R position to position 1. When bridgingthe terminals 51 and 52 any selected resistance is shunted and the timedelay means 74 has no time delay cycle and therefore this allows for adirect electrical path from the positive supply line to the reading unit69, and therefore in such a round there will be no requirement ofminimal time between control stations. i

The central control unit is located at afixed position and is comprisedof a case containing electrical, electronic and mechanical elementscooperating together to control the watchmans round in a fully automaticway. The central control station sets the maximum time the watchman mustrequire for his vigilancy round as it has been preset in an electronictime delay means. The case is a closed assembly provided with a door,closed by a key, through which access is gained to the interiorelements.

The central control station is provided with a power supply 82 (FIG. 7)which may be electrically con nected, or not to the main supply of thepremises wherein the alarm system is set up.

The central control unit sends current through a hand switch and areplay 84 man electronic or electromechanical time delay means 81. Thetime delay means 81 is able to start a time delay cycle upon receivingsupply current and allows flow therethrough when the time delay cycle,which has been programmed in the presetting dial, is completed, anduntil the breaking of the current supply, in which case the time delaycycle suddenly turns back to zero time whether the time delay cycle isat its beginning or it has been completed.

The detailed description of the time delay means whose operation hasbeen described above has been omitted herein, and the detaileddescription of the several electronic components has been omitted also,since these elements, separately considered, are not a part of thepresent invention and are well known in the art.

As explained hereinabove, when ending the round, the watchman connectsthe plug 27'into socket 63 (FIG. 7) in the last central station of thevigilance round, which is the reseting station, and which is connectedto the central control unit. The last central station must receive ashort electrical signal from oscillator 70, as will be explained below,which signal passes through capacitor 85 presenting low reactance asthis is a proper frequency signal. This signal is applied to the coil ofrelay 84 thus activating the same over a short time period, this causingin turn the opening of the armature of relay 84 for a correspondingshort time, and transiently breaking off the electrical supply to thetime delay means 81 and therefore turning back the time delay cycle tozero time to immediately start a new cycle. In the event the watchmandoes not effect the resetting of the central unit in the predeterminedtime, the time delay means completes the time delay cycle, thus allowingthe turning on of the lamp 86 for drawing the watchmans attention.

Simultaneously, the thermal element of a time relay begins to heat abimetal junction 88 which, after some time, acts to activate a ring 89or some other sound alarm means and in turn this builds up a failure inan electro-mechanical counter 90. Simultaneously, a thermal element 91is energized which thus starts to heat the bimetal junction 92 which,after some predetermined time, acts on another general alarm systemlocated at the premises to be protected.

The resetting pulse from the oscillator 70 appears in the plug 27because of the following condition to be noted in FIG. The upperterminal of plug 27 is directly connected to one of the outputs ofoscillator 70; its lower terminal will be momentarily connected to theother oscillator output when passing the finger 49 over the contactingposition 50, thus establishing the following circuit: lower terminal ofplug 27, terminal 41, finger of selector key 43, contactor 50, commonring, terminal 42, lower output of the oscillator, upper output of theoscillator, and upper terminal of plug 27, the oscillator voltageappearing in the terminals of plug 27.

It will be obvious to those skilled in the art that various changes maybe made without departing from the scope of the invention and theinvention is not to be considered limited to what is shown in thedrawings and described in the specification.

What is claimed is:

1. An alarm apparatus comprising: 7

a plurality of fixed control means for providing an electrical referencesample;

a portable control means, having a plurality of comparison elementstherein equal in number to said plurality of fixed control means, forcomparing the electrical reference sample provided by each of said fixedcontrol means with one of said comparison elements; and

a central control means for triggering an alarm means ifa proper signalis not fed thereinto by said portable control means within apredetermined time period;

said portable control means further including a signal means therein forproviding said proper signal to said central control means only when allof the electrical reference samples provided by said plurality of fixedcontrol means have been positively compared by said portable controlmeans in a predetermined order.

2. An alarm apparatus in accordance with claim 1,

wherein said portable control means further includes: advancing meansfor determiningif said electrical reference sample and said comparisonelement being compared thereto are a match and advancing said comparisonelements only after a match has been determined, said match being apositive comparison.

3. An alarm apparatus in accordance with claim 2,

wherein said portable control means further includes:

a timing means having at least one timing element therein for preventingsaid advancing means from functioning until a minimum amount of time asdetermined by said timing element has elapsed.

4. An alarm apparatus in accordance with claim wherein;

said timing means includes a number of said timing elements equal to thenumber of said fixed control means plus one more representing theminimum time between the final one of said fixed control means and saidcentral control means.

5. An alarm apparatus in accordance with claim 3 wherein:

said portable control means further includes a switch means fordisconnecting said timing means.

6. An alarm apparatus in accordance with claim 1,

wherein:

said fixed control means each comprise a resistor and capacitor pair ofa predetermined electrical reactance;

said comparison elements each comprise a resistor and capacitor pair ofapredetermined electrical reactance; and

said portable control means compares the reactances of said fixedcontrol means and said comparison elements by means ofa Wheatstonebridge circuit.

7. An alarm apparatus in accordance with claim 1 wherein:

said fixed control means further includes a socket means attachedthereto for receiving a plug and for electrically connecting said plugwith said electrical reference sample; and

said portable control means further includes a plug means attachedthereto for insertion into said socket means to electrically connectsaid portable control means with said fixed control means.

'8. An alarm apparatus in accordance with claim 1 wherein, in saidcentral control means:

said alarm means comprises at least one alarm light and alarm timingmeans for triggering a second general alarm means if said proper signalis not fed into said central control means within a time period asdetermined by said alarm timing means wherein said alarm timing means isactivated upon triggering of said alarm by said central control means.

9. A method of protecting an area, comprising the steps of:

1. starting the running of a predetermined period of time at a centralcontrol station at the expiration of which an alarm will be triggered ifa proper signal has not interrupted the running of said period of timeprior thereto;

2. conveying to a first comparison station a portable signal givingmeans for providing said proper signal 9 10 only when a program ofcomparisons have been advancing said signal giving means through theencompleted; tire program of comparisons, thereby completing 3.connecting said portable signal giving means to said first comparisonstation and if there is a positive comparison, automatically advancingsaid sig- 5 nal giving means to the second in said program of to Samcomm system and pr( mdmg sald comparisons. proper signal thereto therebyinterrupting the run- 4. conveying connecting said portable signalgiving g of Said predetermined Period of lime means to each subsequentcomparison station and said program of comparisons; and 5. conveying andconnecting said signal giving means

2. An alarm apparatus in accordance with claim 1, wherein said portable control means further includes: advancing means for determining if said electrical reference sample and said comparison element being compared thereto are a match and advancing said comparison elements only after a match has been determined, said match being a positive comparison.
 2. conveying to a first comparison station a portable signal giving means for providing said proper signal only when a program of comparisons have been completed;
 3. An alarm apparatus in accordance with claim 2, wherein said portable control means further includes: a timing means having at least one timing element therein for preventing said advancing means from functioning until a minimum amount of time as determined by said timing element has elapsed.
 3. connecting said portable signal giving means to said first comparison station and if there is a positive comparison, automatically advancing said signal giving means to the second in said program oF comparisons;
 4. An alarm apparatus in accordance with claim 3 wherein: said timing means includes a number of said timing elements equal to the number of said fixed control means plus one more representing the minimum time between the final one of said fixed control means and said central control means.
 4. conveying connecting said portable signal giving means to each subsequent comparison station and advancing said signal giving means through the entire program of comparisons, thereby completing said program of comparisons; and
 5. An alarm apparatus in accordance with claim 3 wherein: said portable control means further includes a switch means for disconnecting said timing means.
 5. conveying and connecting said signal giving means to said central control system and providing said proper signal thereto thereby interrupting the running of said predetermined period of time.
 6. An alarm apparatus in accordance with claim 1, wherein: said fixed control means each comprise a resistor and capacitor pair of a predetermined electrical reactance; said comparison elements each comprise a resistor and capacitor pair of a predetermined electrical reactance; and said portable control means compares the reactances of said fixed control means and said comparison elements by means of a Wheatstone bridge circuit.
 7. An alarm apparatus in accordance with claim 1 wherein: said fixed control means further includes a socket means attached thereto for receiving a plug and for electrically connecting said plug with said electrical reference sample; and said portable control means further includes a plug means attached thereto for insertion into said socket means to electrically connect said portable control means with said fixed control means.
 8. An alarm apparatus in accordance with claim 1 wherein, in said central control means: said alarm means comprises at least one alarm light and alarm timing means for triggering a second general alarm means if said proper signal is not fed into said central control means within a time period as determined by said alarm timing means wherein said alarm timing means is activated upon triggering of said alarm by said central control means.
 9. A method of protecting an area, comprising the steps of: 